3.2.15. dns¶
Enclosing container for DNS resolver data.
vsr running config# vrf <vrf> dns
search¶
An ordered list of domains to search when resolving a host name.
vsr running config# vrf <vrf> dns
vsr running dns# search SEARCH
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The domain-name type represents a DNS domain name. Fully quallified left to the models which utilize this type. Internet domain names are only loosely specified. Section 3.5 of RFC 1034 recommends a syntax (modified in Section 2.1 of RFC 1123). The pattern above is intended to allow for current practice in domain name use, and some possible future expansion. It is designed to hold various types of domain names, including names used for A or AAAA records (host names) and other records, such as SRV records. Note that Internet host names have a stricter syntax (described in RFC 952) than the DNS recommendations in RFCs 1034 and 1123, and that systems that want to store host names in schema nodes using the domain-name type are recommended to adhere to this stricter standard to ensure interoperability. The encoding of DNS names in the DNS protocol is limited to 255 characters. Since the encoding consists of labels prefixed by a length bytes and there is a trailing NULL byte, only 253 characters can appear in the textual dotted notation. Domain-name values use the US-ASCII encoding. Their canonical format uses lowercase US-ASCII characters. Internationalized domain names MUST be encoded in punycode as described in RFC 3492. |
server¶
List of the DNS servers that the resolver should query. When the resolver is invoked by a calling application, it sends the query to the first name server in this list. If no response has been received within ‘timeout’ seconds, the resolver continues with the next server in the list. If no response is received from any server, the resolver continues with the first server again. When the resolver has traversed the list ‘attempts’ times without receiving any response, it gives up and returns an error to the calling application. Implementations MAY limit the number of entries in this list.
vsr running config# vrf <vrf> dns
vsr running dns# server <server>
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Description |
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An IPv4 address. |
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An IPv6 address. |
proxy¶
DNS proxy configuration.
vsr running config# vrf <vrf> dns proxy
enabled¶
Enable or disable DNS proxy. By default, DNS proxy listens to requests on all networks and forwards them to local DNS servers (configured statically or obtained through DHCP).
vsr running config# vrf <vrf> dns proxy
vsr running proxy# enabled true|false
- Default value
true
listen-to¶
Configure networks on which to listen to DNS requests. If not specified, DNS proxy listens to all networks.
vsr running config# vrf <vrf> dns proxy
vsr running proxy# listen-to LISTEN-TO
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Description |
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An IPv4 prefix: address and CIDR mask. |
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An IPv6 prefix: address and CIDR mask. |
forward¶
Configure name servers to forward the DNS requests to. If not specified, requests are forwarded to local DNS servers (configured statically or obtained through DHCP).
vsr running config# vrf <vrf> dns proxy forward
server¶
The address of the DNS servers, can be either IPv4 or IPv6.
vsr running config# vrf <vrf> dns proxy forward
vsr running forward# server SERVER
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Description |
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An IPv4 address. |
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An IPv6 address. |
local¶
Forward DNS requests to local DNS servers (configured statically or obtained through DHCP).
vsr running config# vrf <vrf> dns proxy forward
vsr running forward# local
dns64¶
DNS64 configuration.
vsr running config# vrf <vrf> dns proxy dns64 <dns64>
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An IPv6 prefix: address and CIDR mask. |
client¶
Clients IPv6 addresses.
vsr running config# vrf <vrf> dns proxy dns64 <dns64>
vsr running dns64 <dns64># client CLIENT
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An IPv6 prefix: address and CIDR mask. |
exclude¶
IPv6 addresses to exclude.
vsr running config# vrf <vrf> dns proxy dns64 <dns64>
vsr running dns64 <dns64># exclude EXCLUDE
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An IPv6 prefix: address and CIDR mask. |
mapped¶
IPv4 prefixes to be map in the corresponding A resource record set. If not defined it defaults to any.
vsr running config# vrf <vrf> dns proxy dns64 <dns64>
vsr running dns64 <dns64># mapped [not] PREFIX